Table 2

Evaluation of in vitro antiparasitic activities of CDC/NIIMAL VAC-1-elicited antibodies (inhibition of sporozoite invasion)

AntibodiesAntibody concentrations, ug/ml
50 25
Invasion numberInhibition, %Invasion numberInhibition, %
Preimmune131  (10)0112  (7)0
Freund19  (3)8529  (3)74
Copolymer3  (2)9810  (3)91
Alum15  (2)8923  (4)79
Positive controlNDND2  (2)98
  • Invasion number given as mean number of P. falciparum sporozoites that entered triplicate cell culture with SD given in parenthesis. Inhibition expressed as % relative to preimmune control culture (0%), which was calculated as follows: 100 × [1 − (mean number of invaded sporozoites in test culture/mean number of invaded sporozoites in control culture)]. Preimmune, antibodies purified from preimmune rabbits used as negative control; Freund, antibodies purified from rabbit receiving Freund’s as adjuvant; Copolymer, antibodies purified from rabbit receiving nonionic block copolymer P1005 as adjuvant; Alum, antibodies purified from rabbit receiving aluminum hydroxide as adjuvant. For positive control, mAb against sporozoites (NFS1) was used. ND, not done.